From 72bcbc46a5c385961b9c167db79ad1f38f04e6a7 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 15 Oct 2021 16:05:51 -0700 Subject: [PATCH] mptcp: increase default max additional subflows to 2 The current default does not allowing additional subflows, mostly as a safety restriction to avoid uncontrolled resource consumption on busy servers. Still the system admin and/or the application have to opt-in to MPTCP explicitly. After that, they need to change (increase) the default maximum number of additional subflows. Let set that to reasonable default, and make end-users life easier. Additionally we need to update some self-tests accordingly. Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/pm_netlink.c | 3 +++ tools/testing/selftests/net/mptcp/mptcp_join.sh | 5 ++++- tools/testing/selftests/net/mptcp/pm_netlink.sh | 6 +++--- 3 files changed, 10 insertions(+), 4 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 050eea231528..f7d33a9abd57 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -2052,6 +2052,9 @@ static int __net_init pm_nl_init_net(struct net *net) struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); INIT_LIST_HEAD_RCU(&pernet->local_addr_list); + + /* Cit. 2 subflows ought to be enough for anybody. */ + pernet->subflows_max = 2; pernet->next_id = 1; pernet->stale_loss_cnt = 4; spin_lock_init(&pernet->lock); diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh index 255793c5ac4f..293d349e21fe 100755 --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -945,12 +945,15 @@ subflows_tests() # subflow limited by client reset + ip netns exec $ns1 ./pm_nl_ctl limits 0 0 + ip netns exec $ns2 ./pm_nl_ctl limits 0 0 ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow run_tests $ns1 $ns2 10.0.1.1 chk_join_nr "single subflow, limited by client" 0 0 0 # subflow limited by server reset + ip netns exec $ns1 ./pm_nl_ctl limits 0 0 ip netns exec $ns2 ./pm_nl_ctl limits 0 1 ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow run_tests $ns1 $ns2 10.0.1.1 @@ -973,7 +976,7 @@ subflows_tests() run_tests $ns1 $ns2 10.0.1.1 chk_join_nr "multiple subflows" 2 2 2 - # multiple subflows limited by serverf + # multiple subflows limited by server reset ip netns exec $ns1 ./pm_nl_ctl limits 0 1 ip netns exec $ns2 ./pm_nl_ctl limits 0 2 diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh index 3c741abe034e..cbacf9f6538b 100755 --- a/tools/testing/selftests/net/mptcp/pm_netlink.sh +++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh @@ -70,7 +70,7 @@ check() check "ip netns exec $ns1 ./pm_nl_ctl dump" "" "defaults addr list" check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 0 -subflows 0" "defaults limits" +subflows 2" "defaults limits" ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.1 ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.2 flags subflow dev lo @@ -118,11 +118,11 @@ check "ip netns exec $ns1 ./pm_nl_ctl dump" "" "flush addrs" ip netns exec $ns1 ./pm_nl_ctl limits 9 1 check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 0 -subflows 0" "rcv addrs above hard limit" +subflows 2" "rcv addrs above hard limit" ip netns exec $ns1 ./pm_nl_ctl limits 1 9 check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 0 -subflows 0" "subflows above hard limit" +subflows 2" "subflows above hard limit" ip netns exec $ns1 ./pm_nl_ctl limits 8 8 check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 8